The present invention relates to a bandwidth control device that relays traffic in a way that receives and transits frames in bidirectional flows of traffic and to a bandwidth control method.
There exists a bandwidth control device configured to prevent the traffic exhibiting a high degree of importance from being delayed or discarded by temporarily storing relay target traffic (frames) in a buffer (queue) within the device and performing bandwidth control such as committed information rate (CIR) and priority control on the occasion of reading the frames from the buffer and then transmitting the frames.
In the bandwidth control device, each of flows is identified when receiving the frames from a server, and the buffer is allocated according to every flow on the basis of a preset relay priority level. Herein, if the traffic (frames) arrives in a bursting manner, a shaping function works as a function for averaging transmission rates. The shaping function is a function of buffering the frames over a set output rate in the buffers within the device. Further, an output rule from the buffer involves using the methods such as the committed information rate (CIR) and the priority control.
A technology (refer to Patent document 1) related to the bandwidth control function for, e.g., a variable-length packet exists as this type of conventional technology. Moreover, there is a technology (refer to Patent document 2) that permits a new connection based on a measured traffic size (an amount of traffic) in a multiple access system.
[Patent document 1] Japanese Patent Application Laid-Open Publication No. 2003-198611
[Patent document 2] Japanese Patent Application Laid-Open Publication No. 11-298532